Process of smelting sulfid ores.



N0. 846,498 PATENTED MAR. 12, 1907. G. W. MUNSON. PROCESS OF SMELTINGSULPID ORES.

APPLIGATION FILED MAR. 23, 1906.

3 SHEETS-SHEET 1.

PATENTED MAR. 12, 1907.

C. W. MUNSON. PROCESS OF SMELTING SULFID ORES.

APPLIGATION FILED MAR. 23, 1906.

3 SHEETS-SHEET 2.

in 29000 W 12 7 No. 846,498 PATENTED MAR. 12, 1907 0. W. MUNSON. PROCESSOF SMELTING SULFID ORES.

APPLIOATION FILED MAR. 23, 1906.

3 SHEETS-SHEET 3.

auvcnfoz witnesses anemic UNITED STATES PATENT citric-n."

(JORYDOX w. MVL'NSON, or 15 mm, 01-110.

PROCESS OF SMELTING SULFID ORES.

To all whom it may concern:

Be it known that I, CORYDON TV. MUNsoX, a citizen of the United States,residing at Toledo, in the county of Lucas and State of Ohio, haveinvented new and useful lm' provements in Processes of Smeltin SulfidOres, of which the following is a specification.

My invention relates to 'the. smelting of pyrites or sulfid ores orartificial sulfites earrying gold, silver, copper, or other metalvalues, .the purpose and object being to utilize the fuel elements ofsulfur and iron in the ores to' furnish the heat to smelt themselveswith the use of but little or no extraneous fuel. 1 i

The usual method of smelting practice is a reducing or melting down ofthe ores; but it is well known that the hot-blast smelting of sulfidoresis an oxidizing process, where a large volume of heated air is driveninto the ore body in the furnace under pressure, producing a rapidoxidation of the sulfur in the ores, and an intense heat is developedand maintained by releasing the sulfurous gases as the ores are meltedand driveninto the ore body, these gases combining with the heated oxyen of the air-blast.

The usua l practice is to drive the air-blast into the ore body in thefurnace through separate round openings or twyers, resulting in anunequal oxidation. The blast penetrating the ore mass in the fusing zoneat separate and individual locations tends to produce accretions at andaround the twyeropenings, which interfere with the uniform distributionof the air-blast through the ore mass, thus lessening the efficiency ofthe furnace.

My improved method of supplying the hot blast by which said blast isdelivered into a con-fined circular air-space or annular cham her which.circles the'entire body of ore on the furnace-hearth results indistributing the air evenly and against the exposed surface of the orebody instead of driving the air into the ore at separate twyer-openings.Therefore by this improvedmethod'the air penetrates the ore massuniformly at all points andunder uniform pressure over the entiresurface. An improved form of furnace by which I secure these resultsis-of special construction and is shown and claimed in anotherapplication for patent filed by me November 6, 1905, Serial No; 286,099.

Specification of Letters Patent. Application filed March 23, 1906.Serial No. 307,686.

section.

Patented March 12, 1907.

One of the objects of this invention is to improve the method ofsmelting referred to by confining the hot blast so that it is not freeto pass over the surface of the ore pile, but is held confined in thespace into which it is driven, so that it will be forced under pressureinto the ore body, such pressure or forcing of the air into the ore bodyor charge be-- ing uniformly distributed andnot .directed against orinto the ore in separated locations.

Another object of the invention is to protect the twyers from the moltenmass by preventing the spreading of the charge. 1

.Another object of the invention is to form a limited air-space aroundthe ore charge or heap and to drive the hot blast into said space todrive back into themass of ore the gases which result from the smeltingof the surface portions of the charge.

To these ends the invention consists in the method substantially ashereinafter described and claimed.

In the accompanying drawings Ihave illustrated a suitable apparatus forcarrying out the process claimed herein, said apparatus, however,forming the subject-matter ofthe application above referred to.

In said drawings, Figure 1 is a vertical sectional vew of a furnacewhich may be employed in carrying out my improved method. Fig. 2represents a section on line 2 2 of Fig. 1. Fig. 3 is a View similar toFig. 1, showing a slightly-different form of the shoulder por. tions ofthe sections and also indicating a different height at which the orebody or charge may be maintained during the smelting process. Fig. 4 isa detail outside elevation of one of the interchangeable waterjacketedsections of the furnace, said section having a single twyer integralwith said section. h ig. 5 represents a section on line 5 5, lig. 4.big. 6 is a detail inside elevation of the section shown in Figs. 4 and5. l ig. .7 represents asection on line 7 7 of Fig. 5. ligs. 8 and 9 areviews similarto Figs. 6 and 7, but illustrating a plurality of twyers inthe l igs. 10 and 11 are views similar to 1* ig. 1, but illustratingmodified forms of apparatus which may be employed in carrying out myimproved process.

Similar reference characters indicate the same or similar parts on allof the figures of the drawings.

It is well known that smelting-furnaces are now built with walls ofsectional construction, each section .having one or more twyers;

but so far as I-arn aware the walls of such furnaces are vertical orinclined inward at the 'hearth-sectionl .The feature of'novelty inconnection with I charge-hole 22 I through' which the molten productpasses to the spout 23 for tapping it' off. This hearth-section forms'nopart of section.

my'present invention and maybe constructed in any wel1-known .orpreferred manner.

Its shape in plan may be round or -elongated, ashereinafter described.The vertical" ortion of the hearth.- section re resented 'by- 21 may,however, be forme by egctending'downward the lower vertical art -.of thewater-jacketed metallic portions 0 thefurnace-wall far enough to formthe hearth.-

The metallic portion of the furnace is supported on the wall and iscomposed of a plurality of removable sections, each of which is hollowto form a water-jacket. Connections for supplying .thesections withwater are not shown, as they may be any form, such .as commonly employedwith. water-jacketed furnaces. The sections may be secured together andto the wall 21 suitable means, such as a band, (indicated at 24; in Fig.1.)

- Each water-jacketed section, when con structed as shown in Figs, 1, 2,4, 5, 6, and 7, comprises an 'upper portion 25 and a lower portion 26 atan obtuseor. other suitable angle thereto, so that when six of suchsections are assembled, as in Figs. 1 and 2, the lower portion of thechamber inclosed said sections flares or spreads'outwardly, thus givingan enlarged hearth area with inwardly-sloping upper walls at such anangle that when ore is iled on the hearth even to a height that wlllreach the angle a: where the portions 25and 26 meet the natural inclineof fall of the sides of the pile or heap of ore will not reach the innersurface of said sloping walls. Preferably each section is formed with alower edge portion 27 to rest-onthe side 21 of the hearth-section; whichortion 27 is parallel with the portion 25 al fhough offset therefrom by'the intervening inclined or flaring portion 26, or this part 27 of thesection maybe extended downward to form the hearth-section 21', as abovementioned. Said inclined or flaring portion'is formed with atwyer-opening -(or a plurality of such openings, as in Figs. 8 and 9) toreceive the airblast through tubes or nozzles 28 from a suitable sourceof supply of heated air, such as a hot-air box 29, surrounding thebrick'part 30 (if the furnace resting on the metallic sections. Thesupply of; hot air at the proper temperature may be obtained by means ofany suit-- able apparatus.

If desired, an inclosing bandBl may surround the joint between the upperends of the metallic sections and brickwork, which band may of course beof any height, even to forming a complete jacket for the brickwork.

The outer end of each twyer is preferably round, as at 32, for theconnection of the tube 28, and the Walls converge vertically (see Fig.5) and diverge horizontally to the inner end 33, (see Figs. '6, 7,8, and9,) so

hereof these portions 26 may be either as straight .or curved inclines;but it is essential that the flare or incline from the .angle a:

shall be greater relatively to the vertical than the natural incline offall of the sides of the ore body, so that when said body is fused andkept supplied with fresh charges there will always be preserved anair-space between the surface 01 the fusing mass and the mouth of thetwyers, whether the hearth be supplied with ore to a point below theangle as or even to a point above it, as indicated in Fig. 3. If theores are loaded up into the neck of the furnace above-the angle m andthe blast driven into theair-space just inside the twyers, said blastbeing continuous and encircling the entire ore. body, the effect of suchblast is to penetrate the surface of the ,ore body evenly and to bedistributed uniformly and carry down the values into the matte or sla'g,savmg a much higher percentage than can be'don'e when there isanydeflection of the blast upward or when penetrating the ore body atseparate points from the usual form of round twyers spaced apart. Withthe air-space so confined and encircling the ore bod or charge theformation of the twyers with widened or laterallyelongated'inner ends isnot indispensable, as the contracted neck of thefurnace so confines theair that it is evenl distributed in said space undersubstantial yuniform ressure at all points around the inclined si es of the'chargebut I prefer to employ twyers of the form shown and described forseveral reasons, one being that their widened inner ends cause the blastto eflect a more even penetration of the surface upon which it impingesand more uniformly'reduce the ore .IIO

and carry the values down intothe matte or slag. a

The supply. of ore may be given to the fur- '1, 3, and 10 and alsohaving means for carrynace by any suitable meansior through any suitableopening .atthe top of the furnace, (not shown.) an initial chargebeingmade, and. succ-asive small quantities supplied at short intervals.

11' the height of the charge is such that its sides do not reach theneck as, as indicated in Fig. 1, the blast of air and the fusing zone offlame confined by the inclined surface 26 above the mouths 33 ofthe'twyers, so that the mantle of flame approximately follows theinclined sides of the charge or heap and results in greater efliciencythan if such blast was blown into abody of ore, covering thetwyer-opening, as is done in usual practice. l In this case the specialor elongated form of twyer described is of great utility, since theentire set of twyers causes a practically continuous blast around. thecharge or heap to penetrate the surface and carry down the values.

A special advantage of the preservation of the confined air-spaceadjacent the twyers is that said twyers are protected from the oreclogging them or the molten mass, which will always flow below them,there being therefore no liability of any of said twyers being cloggedor of any of the molten mass running into them, a condition which is asource of much trouble under present practice.

In Fig. 1.0 I have illustrated another form of furnace which may beemployed in carrying out my improved process. In said figure-the wallsof the furnace are composed of one circular section water-jacketed fromtop to bottom and with the hot-air box 291, surrounding the furnace in alower plane than in Fig. 1, so as to communicate directly with the orewithout the intervention of twyers. Leading to said hot-air box 291 isan air-pipe. 34. for conveying a hct'air blast to the box 291. Withinthe box 291 there maybe suitable braces 35 to better support the weightof the upper portions of the water-jacketed section. I

In Fig. 11 I have represented a furnace differing somewhat from thatshown in Figs.

ing out a further step of my invention. In said Fig. 11 thefurnace-walls are shown as in two entirely-separated water-jacketedportions 251 and 271 with a clear annular space 261 between them,therefore dispensing with lawyers. i he lower edge of the upper portion251 serves to prevent the spread of the ore in the same manner as theneck or angle a: in the other figures, and the annular airspace for theblast under pressure is confined to thc space within the hot-air'box 291and below said. lower edge of the wall portion 251. In said Fig. 11 atubular chute 36 leads into one side of the box 291 and contains a screwconveyer 37, operated by. any suitable means. A hopper 38 connects withthe. outer portionof the chute and is provided with a cover adapted tobe tightly closed after it has been filled with concentrates. Instead ofbriqueting fines and concentrates before smelting, so as to feed in withthe ore at the top of the furnace, the same may be placed in'the hopper38 and the cover closed and the screw ccnveyer 37 operated to force theconcentrates into the box or chamber 291, where they will be taken up bythe hotair blast and forced into the fusing zone encircling the heap ofore.

As the tines and concentrates thus forced into tlre confined air-spacearound the heap carry a high percentage of sulfur and iron, they arefused at once, releasing the sulfurous gases into the airchamber, andare oxidized by the air from the hot blast and driven into the meltingore in the fusing zone, thus utilizing to the greatest efiiciency theheat units developed from the fuel elements of sulfur andiron containedin the sulfid ores fed to the furnace and producing an intense heat inthe fusing zone of the furnace and a rapid smelting of the ores.

Carbonaceous. fuel, such as powdered. coke or charcoal or other forms offuel, may be fed and driven into the confined air-space with the finesor concentrates or by itself, so as to increase, the temperature of thefusing zone. Such fuel cannot escape. before doing its work, becausethere is no opportunity for its immediate escape from the confined airspace.

WhileI have forconvenience shown the feed-chute as opposite the air-pipe34, it is to be understood that they maybe closely ad jacent to eachother, or the feed of the concentrates might be into the air-pipe, sothat said concentrates would be blown in with the air instead of beingtaken up by the air in the box'flgl. In either case the concentrates godirectly to the surface of the melting ore on the hearth.

Having now described my invention, I claiml 1. The process of smeltingsulfid ores, which consists in forming and maintaining a heap of the orewith inclined sides from the base upward, forming'a limited and confinedair-space around the base, of the heap, and forcing a heateo air-blastinto said spacer 2. The process of smelting suifid ores,

.which consists in forming and maintaining a low charge with inclinedsides from the base upward, preventing the spread ofthe chargeat a pointabove its base and maintaining an air-space surrounding the saidinclined sides including the base thereof, and forcing air into saidspace and upon said inclined sides. 3. The process of smelting suliidores, which consists in forming and maintaining a heapof the ore withinclined sides fromthe base upward, heatingthe heap to a temperaturesufiiclent to enable a ortion of the sultherein to be release and tocombine roo IIO

with oxygen, forcing air upon the exposed sides of the heap includingthe base thereof, thereby effecting combustion of a portion of thesulfur and enveloping the heap in a mantle of [lame and fusing the outerportion oi the heap, and confining the fusin zone'of flame to theapproximate incline sidesof the heap, within the confined air-space.

4. The process of smelting sulfid ores, which consists in forming andmaintaining a confined air-space between the walls of a furnace and thesides of a low ore charge around the base thereof, and forcing a hot-airblast into said space. i

5. The process of smelting sulfid ores, which consists in forming andmaintaining a confined air-space between the walls of a furnace and thesides of a low ore charge around the base thereof, and uniformlydistributing hot air under pressure in said space to drive back into themass on the furnace-hearth the gases resulting from the melting of thesulfur in portions of such charge. p

6. The process of smelting sulfid ores which consists in forming andmaintaining a low charge of the ore with inclined sides,

' forcing a heated air-blast against the surface of said charge aroundthe base thereof, and

preventing the direct assa e of the air upward over the said sur ace 0the charge.

7. The recess of smelting sulfid ores, which consists in forming andmaintaining a heap of the ore with inclined'sides from the base upward,forming an upwardly-convergingoonfined air-space surrounding the base ofthe heap, and forcing a heated air-blast into said space.

8:1 The process I of smelting sulfid ores WhiCll CQIlSlSiZS informingand maintaining a heap of the ore with inc ined sides from the baseupward, forcing a heated air-blast against the surface of the heapadjacent to its base, and preventing the spread of the ore above thatpart of the surface into which the blast is driven.

9. The process of smelting sulfid ores, which consists in forming andmaintaining a heap of the ore with inclined sldes from the base upward,forming a limited and confined air-space around the base of the heap,forcing a heated air-blast into said space and simultaneously feedingfuel to said space.

' 10. The process of smelting sulfid ores, which consists in forming andmaintaining a hea of the orewith inclined sides, forminga limited andconfined air-space around'the' heap, forcing a heated air-blast intosaid space and simultaneously feeding fines and concentrates to saidspace.

In testimony whereof I have affixed my "signature in presence of twosubscribing witnesses.

" Witnesses:

'YCORYDON w. MUNsoN;

